You need to be in Manual mode (that's the M on the dial with the letters and pictures- NOT AV, TV, A, S or AUTO

in order to change the shutter speed you rotate the scroll by the shutter release (same as you used to change the aperture in the AV mode)

in order to change the aperture (f stop) you rotate the scroll by holding down the AV button on the back of your camera and rotating the scroll.

I suggest also being in MANUAL FOCUS! Your camera will not be able to see what it is taking the photo of in the dark- so throw the camera into MANUAL focus and look through the viewfinder and focus your image. (you will need to provide light in order to focus manually as well)

Your exposures should be around the 10" to 30": seconds- you can use the BULB setting to do longer then 30 seconds. (30") If the shutter sounds quick it is possible you're on 1/30 or 1/10. Make sure your shutter speed reads " after the number which is the symbol for seconds.

SELF TIMER: If you only can use yourself for the pictures (you don't have a buddy), That is a semi circle with a line and a dot on the back of the camera. Click that button. it will give you a few seconds before the camera releases the shutter to get into place.

Remember:

your camera needs to be stationary. (tripod, table, chair)

You will get different effects by pointing your lights (sharper- directional) towards the camera then when you shine it on a subject (broader, softer, reflective)

You should have movement in your image, this movement will be recorded on your image sensor while you draw with light.

if your picture is too light either shorten your exposure time, make your scene darker, or make your aperture smaller (larger number)

if your picture is too dark, either lengthen your exposure time, make your scene brighter, or make your aperture larger (smaller number)

your scene should be very dark

try different types of lights: finger lights, flashlights, cell phone (iflashlight app),etc. if you're home sparklers or candles can be fun- but be safe.

laser lights are actually not continuous lights and they blink really fast so if you get a dotted line, that's why

Include the four following types of drawing with light:Use flash (goes off at the beginning of the exposure)Use direct light- shine the light source towards the cameraUse indirect or reflected light- shine the light towards the subject to highlight the subjectTry putting the same subject in the image multiple times

Additionally:Try a few different things... if you need inspiration you can google:"light drawings" "light trails""drawing with light"